How to have perfect timing, according to science

Judy Woodruff: Now to the NewsHour Bookshelf. So, when do you work best? Are you a night owl or an early bird? Jeffrey Brown explores these questions with author Daniel Pink.

Jeffrey Brown: There are plenty of how-to books out there. Now comes a when-to, the best time of day to take an exam, say, or have a medical procedure, and big life decisions, getting married, getting divorced, quitting a job.

Jeffrey Brown: Let me start with a when question for you. When did you get interested in this, and why?

Daniel Pink: Well, I realized that I was making all kinds of when decisions myself, so things like, when in the day should I exercise? When should I abandon a project that's not working?

And I was making them in a pretty haphazard way. And I figured I could make them in a better way. And I started looking at this research. And there is a mountain of research out there across many, many domains that allow us to make evidence-based, systematically smarter, shrewder decisions about when to do things.

Jeffrey Brown: Smarter, shrewder. That subtitle, "Science," right?

Daniel Pink: Sure.

Jeffrey Brown: So, that's the data that you're looking at.

Daniel Pink: Oh, yes, yes, yes.

It's data that comes in the field of economics, social psychology, but also cognitive science, anesthesiology, endocrinology. There's a whole field of chronobiology. Linguistics gives us some clues.

So, this research is all over the place. But in these different disciplines, they're asking very, very similar questions.

Jeffrey Brown: All right, so daily routines first. You're teasing out some of the patterns of our lives.

Daniel Pink: Well, what it shows is that both our mood and our performance follow a fairly regular pattern across a day.

So we usually have a peak, a trough, and a rebound. So our peak for most people is in the morning. We have a trough in the early afternoon, and then we have this rebound, recovery period later in the day.

Now, for people who are night owls, they go through it in the reverse order. But what the research tells us is that we should be doing our analytic work, our heads-down, lockdown work during the peak.

During the trough, it's not good for very much. We should be doing our — we should be avoiding going to the hospital and answering our routine e-mail. And then, during the recovery, we have an elevated mood, but we're less vigilant than during the peak. And that makes it a very good time for things like brainstorming and other kinds of creative work.

And just moving our work just a little bit can make a big difference. There's research showing that time of day explains about 20 percent of the variance in human performance on workplace tasks. So timing isn't everything, but it's a big thing.

Jeffrey Brown: So the important thing is knowing who you are, in a sense, right?

Daniel Pink: Yes.

Some of us have what are early chronotypes. We're larks. Get up early, go to sleep early. Some people have evening chronotypes, owls, go to sleep late, wake up late.

Most of us are kind of in the middle, what I call third birds. But the people who are larks and third birds peak, trough, recovery fairly predictably. The people who are owls, recovery, trough, peak fairly predictably.

Jeffrey Brown: There is so much fun to reading this, and then there's the scary things like, don't go have a medical procedure in the afternoon. That's not a good idea.

Daniel Pink: That is really not a good idea.

It's kind of alarming if you look at some of the research. Anesthesia errors, four times more likely at 3:00 p.m. than at 9:00 a.m.

Endoscopists find half as many polyps in routine colonoscopies in afternoon exams vs. morning exams. Nurses less likely to wash their hands, physicians more likely to prescribe unnecessary antibiotics in the afternoon.

Jeffrey Brown: Yes.

So, speaking of afternoon, taking breaks is clearly — breaking up the day, which leads to the question of naps, for example, everyone is familiar with that. But you're not talking just about taking a nap, but very specific amounts of time, right?

Daniel Pink: Yes.

The research on naps shows that naps are actually good for us. I'm a convert on this in that any time I took a nap myself, I would always wake up feeling both groggy and deeply ashamed of myself.

(LAUGHTER)

Jeffrey Brown: Right.

Daniel Pink: So, for being so lazy.

And it turns out I was doing it wrong. The ideal nap…

Jeffrey Brown: We don't have the siesta idea.

Daniel Pink: No, not at all. No, I have both the hyper-puritanical and hyper-masculine approach to things, which is a toxic mix.

But what we know about naps is that 10 to 20 minutes is actually the ideal time to take a nap. You get all of the benefits of a nap. I think of naps as Zambonis for our brains. They basically smooth out the nicks on our mental ice.

But without any of what's called sleep inertia. And the ideal nap is something called the nappuccino, where you have a cup of coffee first. Set your alarm for maybe 25 minutes. Take a nap. By the time you wake up, the caffeine will be hitting your body.

Jeffrey Brown: Yes, I read this. And this one really hit me.

Daniel Pink: It works.

Jeffrey Brown: It works. Drink the coffee, then take the 20-minute nap.

Daniel Pink: Right.

Jeffrey Brown: Now, at the end of every chapter, you have what you call the time hacker's handbook. And you are really giving people tips. You think it's practical enough that we can change our lives.

Daniel Pink: Sure. Absolutely.

I don't think you can transform your life. If you are overweight and lazy, changing your approach to time isn't going to convert you in that way. But what I'm trying to do here is that there's some really amazing science out there that gives us insights into who we are.

But I find that if you can take some of that science and put it into place in your own life, it's meaningful and you understand the science better.

Jeffrey Brown: So have you changed your own life, found time?

Daniel Pink: Oh, absolutely.

So, I am a convert on breaks. I always write down two breaks in the afternoon that I'm going to take. I make a break list. I have also been a convert on good news and bad news. I always gave the good news first, because I wanted to be a nice guy. But what you really want to do is give the bad news first, end on that elevation.

That's one of the things that endings do for us. So, I have become not only a break-taker, but the king of delivering bad news first.

(LAUGHTER)

Jeffrey Brown: The book is "When- The Scientific Secrets of Perfect Timing."

Dan Pink, thanks so much.

Daniel Pink: My pleasure.

Judy Woodruff: Fascinating. I'm getting that book.

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